Automatic unlocking device for rolling stock couplers

ABSTRACT

An automatic unlocking device for rolling stock couplers to make the couplers of travelling trains separable by lifting the fastening cotters from them, which consists of a base stand installed at the side of the railway track, a boom mechanism composed of parallel links movable along the railway track and arranged on the said base stand tilting freely towards the railway track, and a robot which is hung from the boom mechanism and is provided with devices for unlocking couplers automatically, so that the robot may be inserted towards any desired couplers of a travelling train and unlock them successively by lifting up the fastening cotters from them by means of its unlocking devices.

Unite States Patent [191 Yamazaki et al.

AUTOMATIC UNLOCKING DEVICE FOR ROLLING STOCK COUPLERS Inventors: Shigezo Yamazaki, Tokyo; Mitsuru Wakao, lwatsuki; Kenichi Inami, Kawasaki, all of Japan Assignees: Japanese National Railways;

Kayabakogyokabushikikaisha, both of Tokyo, Japan Filed: Jan. 28, 1974 Appl. No.: 437,001

Foreign Application Priority Data Jan. 30, 1973 Japan 48-11579 U.S. Cl. 213/211, 213/218 Int. Cl. B6lg 7/04 Field of Search 213/75 R, 211-219 References Cited UNITED STATES PATENTS 6/1912 Biaettnar 213/75 R 3,160,286 12/1964 Wilson 213/211 X 3,682,325 8/1972 Peterson et a1..... 3,750,897 8/1973 Murato et a1.

Primary Examiner-M. Henson Wood, Jr. Assistant Examiner-Gene A. Church Attorney, Agent, or Firm-Saul Jecies 5 7 ABSTRACT An automatic unlocking device for rolling stock couplers to make the couplers of travelling trains separable by lifting the fastening cotters from them, which consists of a base stand installed at the side of the railway track, a boom mechanism composed of parallel links movable along the railway track and arranged on the said base stand tilting freely towards the railway track, and a robot which is hung from the boom mechanism and is provided with devices for unlocking couplers automatically, so that the robot may be inserted towards any desired couplers of a travelling train and unlock them successively by lifting up the fastening cotters from them by means of its unlocking devices.

10 Claims, 9 Drawing Figures PATENTEL, SEC I 7 I974 SHEET 10F 7 FIG.

PATENTEL m 1 71m SHEEI 2 BF 7 FIG.2

Pmmm 3.854.598

SHEET 3 BF 7 FiG.3

PATENTEL DEC! 7 I974 SHEET 0F 7 FI.G.4

AUTOMATIC UNLOCKING DEVICE FOR ROLLING STOCK COUPLERS BACKGROUND OF THE INVENTION The present invention deals with automatic unlocking equipment for rolling stock couplers, which lifts the fastening cotters from the couplers of rolling stock travelling in coupled condition and brings them to a suitable position for separation.

Generally speaking, railway waggons are arranged in trains according to the destination of their cargoes and may be arranged several times at various stations before they reach their destination. Principal railway junctions, therefore, are provided with marshalling yards where the rearrangement of trains occurs. The problem of these marshalling yards is how the separation and re-coupling of waggons may be practiced efficiently and safely.

In the separation and re-coupling of waggons, normally couplers and brake hoses connecting adjacent waggons must be separated and re-coupled individually. The separation and re-coupling of brake hoses may be practiced while the waggons are stopped on the arrival line or classification line, while re-coupling of the couplers may also be carried out automatically if one Waggon, after its fastening cotter is lifted up from the coupler, is permitted to collide with another stationary Waggon at a speed within a certain range, because the couplers of both waggons impact, then tend to separate from each other and eventually the fastening cotter falls in place naturally. These operations, therefore, may be carried out without much danger. In contrast, if fastening cotters are lifted from their couplers ready for separation beforehand while the waggons are stopped on the arrival line, there is a danger that the fastening cotters may fall down naturally to recouple the couplers as the waggons push or pull each other due to the starting impact which occurs when the waggons are pushed towards the classification line. For this reason, the separation of couplers must be practiced while they are in contact and while the train is being pushed towards the classification line. Yard operators, therefore, must lift upfastening cotters sucessively by hand from couplers to be separated according to the waybill of the train while moving back and forth at the side of the train. This work is not only very laborious, but also very dangerous as it must be done at the side of travelling trains.

For labor saving as well as the prevention of danger, it can be of great help if the lifting of fastening cotters is automated. If the equipment becomes very complex due to such automation, however, it may not be applied conveniently to many small marshalling yards such as plane yards, even though it may be applied to the few large ones such as hump yards. Thus, it is desired that the mechanization of this kind of operation be accomplished in a-simple manner.

SUMMARY OF THE INVENTION From the above point of view, the purpose of the present invention is to offer an automatic unlocking device for rolling stock couplers, making it possible by means of fixed equipment installed on the ground to locate couplers to be separated among those of travelling trains, and to lift the fastening cotters from those couplers automatically.

To achieve this, the equipment according to the present invention consists of a base stand which is installed at the side of the track leading from the arrival line towards the classification line, a boom mechanism which is supported by the base stand tilting freely towards the track and incorporating a link mechanism movable also as required parallel to the track, and a robot which is hung from the boom mechanism and provided with various fingers having the function of unlocking couplers automatically. This novel equipment may not only be installed readily in a very small trackside areas, but also makes it possible to lift fastening cotters from the couplers of travelling trains and keep them ready to separate. Also, the robot may be applied to couplers of various types by modifying its automatic unlocking mechanism.

In order to clarify the above and other purposes, features and performance of the equipment of the present invention fully, further explanation will be given in the following referring to a preferred embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS:

FIG. 6 is a detailed side view of FIG. 5 FIG. 7 is a side view showing the locating finger part of the robot in further detail.

FIG. 8 is a front view showing the unlocking finger part in further detail; and

FIG. 9 is a back view showing the upper lock lifting finger part of the robot in further detail.

DESCRIPTION OF THE PREFERRED EMBODIMENT:

An automatic unlocking device (10) for rolling stock couplers according to the present invention is shown in FIG. 1 as it is applied in practice.

This automatic unlocking equipment (10) of couplers consists of a base stand (1 1) which forms the supporting part, a boom mechanism (12) which is arranged to tilt freely taking the base stand as a supporting point and a robot (13) which is hung from the top of the boom mechanism (12). These parts are designed not to protrude beyond a certain boundary (l4) indicated with dotted lines in FIG. 1 when they are in the normal position.

When the present equipment (10) is installed at the railway 15) side, the base stand (11) which forms the I supporting part is fixed at the lower surface on the track base (16) and carries supporting brackets (l7) (l8) (19) on the upper surface.

The boom mechanism (12) consists of a link case (20), a pillar (21) and parallel links (22) connecting the pillar to the link case. The link case (20) has an arm (23) extending as a single body from its side and the top of the ,arm (23) is supported, oscillating freely around a shaft (24), by the supporting bracket (17) of the base stand (11). A tilt cylinder (27 is incorporated between the middle of the arm (23) and the supporting I (28) is travelling, as shown with dotted line in the figure.

As seen in FIGS. 3 and 4, the parallel shift links (22) connecting the link case and the pillar (21) consist of two crank arms (29) (30) which are fixed at the upper and lower parts of the link case (20), respec tively, and two parallel links (31) (32) which are arranged relative to these crank arms. The base end shaft or rotation axis (33) of the upper crank arm (29) is supported by one of the side walls and an inner partition wall (34) of the link case (20), while shaft (35) of the lower crank arm (30) is supported by both side walls of link case (20). Both the shaft (33) (35) protrude at one end beyond the link case (20) into the drive case (36), where they are provided with gears (37) (38}of identical diameter interlocking simultaneously with a timing gear (40) which is 'suppported by the link case (20) on a shaft (39). Also, the rotation shaft (35) of the lower crank arm (30) is connected to a rotary actuator (41) fixed to drive case (36) so that, by the rotation of the actuator (41), the upper and lower crank arms (29) (30) may be allowedto oscillate always in parallel, at identical speeds and in identical directions.

The two parallel links (31) (32) are made of square bars having round shaft parts (42) (43) at the middle. They are supported by the link case (20) as they are inserted loosely at the'round shaft parts (42) (43) into bearings (44) (45) which are arranged, oscillating freely, in upper and lower positions parallel to the rotation shafts (33) (35) of the crank arms (29) (30) The parallel links (31) (32) are connected at the base end to crank pins (46) (47) of the crank arms (29) (30) and at the top end to the said pillar (21) by means of shafts (48) (49), so that the pillar may be kept upright.

Thus, if the crank arms (29) (30) oscillate within an angle or (refer to FIG. 4) by manes of gears (37) (39) with rotation of the said rotary actuator (41), or if the pillar (21) travels within a distance 1 due to an outside force, the parallel links (31)(32) oscillate around the bearings (44}(45) while sliding there, so that both of their. top ends may be moved horizontally. As a result, the pillar 21) may be moved horizontally while being kept upright.

The robot (13) is hung with a shaft (51) oscillating freely to a hanger fixed to the top end of the pillar (21). A levelling cylinder (54) is pivoted with shafts (52) (53) between the robot (l3) and the hanger (50). Another levelling cylinder (55) which forms a pair with the levelling cylinder (54) is pivoted with shafts 56) (57) between the supporting bracket (19) of the base stand (11) and the arm (23) of the boom mechanism (12). As the boom mechanism (12) oscillates around the shaft (24) according to the extension or retraction of the said tilt cylinder (27), these levelling cylinders (54) (55) perform reciprocal motions (as one is extended, the other is retracted) while exchanging their actuating fluids, so that the robot (13) may always be kept upright irrespective of the inclination angle of the boom mechanism (12).

In the said application example, as seen in FIGS. 5 and 6, the robot (13) consists of a main arm (58), two supporting arms (59) (60) which extend downwards as a single body from the main arm, locating fingers (61) and lock release fingers (62) (63) which are all arranged on the supporting arm (59) and a lock lift arm (64) which is movable up and down along the main arm (58) and carries lock lift fingers (65) (66). As was stated already, the robot is hung on the hanger (50) of the pillar (21), namely by means of a bearing unit (67) arranged at the upper part of its main arm (58).

As seen in FIG. 7, the locating fingers (61) arranged on the supporting arm (59) incorporate a first finger (68), ashort one, and a second finger (69), a long one. The base ends of these fingers (68) (69) are supported by shafts (71) (72), oscillating freely to the left and the right, respectively, on a supporting plate fixed to the supporting arm (59). A hanging plate (73) extending downwards from the supporting plate (70) supports at the lower end a locating cylinder (74), which has a spacer (76) at the top of its rod Since the pins (80) (81) at the tops of arms (78) (79) extending from the base ends of the said fingers (68) (69) are fitted into a groove (77) of the spacer (76), the fingers (68) (69) oscillate around the shaft (71) (72) according to the extension or retraction of the locating cylinder (74) so as to fold as indicated in the figure, or open to the left and right.

Lock release fingers (62) (63) are to fit with and push up the release levers (83) (refer to FIG. 1) of couplers (82) on waggons (28) and bring them to a mov able position by releasing them from the chain locks. The upper and the lower lock release fingers (62) (63) may be employed for waggons of upper and lower operating types, respectively. As seen in FIG. 8, therefore, these lock release fingers (62) (63) are fitted, sliding freely, to the upper and the lower parts of the supporting arm (59) and joined to each other with a connecting rod (84). The release cylinder (85) which actuates these lock release fingers (62) (63) is fixed to the supporting arm (59) with a supporting plate (86) and its rod (87) is connected at the top end to push-up ring (88), which is inserted loosely in the supporting arm (59). Thus, the lock release fingers (62) (63) are allowed to slide up and down along the supporting arm (59) as the lock release cylinder (85) extends or retracts. It is recommendable to bring the lock release fingers (62) (63) to the working position only when they are used, while keeping them normally in the passingposition asthawn in FTGS. 5 and 8 so as to prevent them from touching waggons when the equipment I0) is inserted between coupled waggons. In this example,

therefore, the top ends of screw rods (19) (92) arranged on the lock release fingers (62) (63) are fitted in cam grooves (89) (92) which are arranged on the supporting arm (59). Thus, with the push-up motion of the lock release fingers (62) (63) actuated by the lock release cylinder (85), these fingers may be automatically turned to the working position from the passing position.

As shown in FIGS. 5 and 6, the lock lift arm (64) having lockrlift fingers (65) (66) is fitted at the upper end with a shaft (93) oscillating to the supporting plate (94), which moves up and down along the said main arm (58) by means of a roller (95). The lock lift fingers (65) (66) arranged on the lock lift arm (64) draw the fastening cotter (109) (refer to FIG. 1) of Waggon (28) from the coupler (82) and make the lock release ready. Like the said lock release fingers (62) (63), the upper and the lower lift fingers (65 (66) work for waggons of upper and lower operating types, respectively. In order to permit the lock lift fingers (65) (66) to perform such a function, the said supporting plate (94) is connected by a shaft (96) at the lower end to the base end of a lock lift pushing cylinder (97), the rod (98) of which is fixed at the top end to a connecting device (99) arranged on the lock lift arm (64), so that the lock lift fingers (65) (66) may be pushed to a suitable position to meet the fastening cotters (109) of couplers (82) as the lock lift arm (64) oscillates around the shaft (93) with the extension of the lock lift cylinder. The connecting plate 100) between the main arm (58) and supporting arms (59) (60) carries a lock lift cylinder (101) fitted with a shaft (102) and the rod (103) of the lock lift cylinder (101) is connected at the top end to the supporting plate (94) by a shaft (104). Thus, the lock lift fingers (65) (66) may be lifted by the extension of the lock lift cylinder through the medium of the supporting plate (94) and lock lift arm (64) to draw up the fastening cotter (109) from the coupler (82) and bring it to a position ready for lock release.

Among these lock lift fingers (65)(66), the lower one (66) has no chance of contacting waggons when the equipment is inserted between coupled waggons and therefore it is fixed to the lock lift arm (64) as a single body, while the upper one (65) may contact waggons in such a case and therefore may oscillate freely on the lock lift arm (64) through the medium of a reception cylinder (105) (65) (66) shown in FIG. 9. Also, the spring (106) is arranged between the cylinder and the coupling device (99), so that the lock lift finger (65) may be kept normally at the working position due to the force of the force of spring (106) and be turned against the spring (106) to the passing'position only when the lock lift arm (64) is folded by retracting the lock lift pushing cylinder (97) and a fastening piece (107) arranged on the reception cylinder (105) of the lock lift finger (65 comes in contact with the stop rod (108) extending from the supporting plate (94).

The automatic unlocking equipment thus devised according to the present invention may be applied to the couplers of travelling waggons in the following manner.

As soon as the couplers of any waggons to be separated from a train which is pushed by a yard locomotive come in front of the equipment (10), a starting signal is given. It may be given by hand as required to the equipment (10) according to the waybill of the train.

It may also be given automatically by means of a simple electronic computer which memorizes the train waybill.

Upon the starting signal, firstly the tilt cylinder (27) of the equipment (10) extend to incline the boom mechanism (12) until the robot (13) reaches the stipulated position between the waggons while keeping the robot upright by means of the levelling cylinder (54) (55), At the same time, an instruction signal is given to switch a solenoid valve (110) arranged on the supporting arm (59) of the robot (13) (refer to FIG. 7) and, as the locating cylinder (74) compresses, the locating fingers (59) (60) open back and forth.

Thus, once one end of a Waggon which is pushed by a yard locomotive comes in contact with the top end of the short finger (68), the robot (13) will move horizontally with the travelling wagon due to the parallel links (22) as the top end of the finger (68) is pushed by the end of the Waggon, while keeping the relative position between the robot (13) and the coupler unchanged. At the same time, if the robot (13) tends to proceed faster than the Waggon due to the impact from the latter, the long finger (69) will contact the top end of the preceding Waggon and prevent the robot from proceeding too fast, thus avoiding in combination with the short finger (68) any deviation in relative position between the robot (13) and the coupler.

Meanwhile, oncethe end of the Waggon contacts the top end of the short finger (68), its roller reception (111) is pressed to some extent to close a limit switch 112 refer to FIG. 7) arranged there and this is detected immediately by the robot (13), which receives the starting signal for sequence operations. This starting signal is then transmitted to a solenoid valve (114) controlling the lock release cylinder through the solenoid control mechanism (113) arranged on the main arm (58) of the robot (13) as shown in FIG. 5.'When the solenoid valve is thus switched, the lock release cylinder (85 expands to lift the lock release fingers (62) (63) while turning them along the cam grooves (89) to the working position from the passing position so as to enable either of them (62) (63) to push up the release lever of the Waggon and make it movable, i.e., bring it to a position ready to unlock by releasing the fastening cotter from the chain lock.

Next, when this operation is over, either of limit switches (115a) (115b) arranged on the lock release fingers (62) (63) is accompanied by shutting of and this signal is transmitted to a solenoid valve (116) controlling the lock lift pushing cylinder (97) through the said solenoid control mechanism (113). Thus, the lock lift pushing cylinder (97) starts to extend and the lock lift arm (64) is turned around the shaft (93) and either of the lock lift fingers (65) (66) is pushed out to a posi tion fitting the lock lifter of the coupler. Accompanied by operation of the upper lock lift finger (65 the fastening (107) leaves the stopper lever (108) and the upper lock lift finger (65) is turned automatically by the force of the spring (106) from the passing position to the working position to fit the lock lifter of the coupler.

Then, when the above operation is over, the lock lift arm (64) closes a limit switch (117) arranged on the supporting plate (94) and the signal from the limit switch (117) is transmitted to a solenoid valve (118) controlling the lock lift cylinder (101) through the solenoid control mechanism (113). As soon as it is thus switched, the lock lift cylinder (101) extends to lift up the lock lift fingers (65) (66) together with the lock lift arm (64), so that the lock lifter and eventually the fastening cotter is pulled up and the coupler is made ready for release.

When such a series of operations is over, the solenoid reset signal, as one of the sequence operations, is passed to all the solenoid valves (114) (I16) (118) through the control mechanism (113) to switch them to the starting position. Thus, the lock lift pushing cylinder (97) retracts to withdraw the lock lift fingers (65) (66) from the lock of the coupler. At the same time, the lock cylinder (101) also retracts to bring them back to the starting position, while the lock release fingers (62) (63) are brought back to the passing position by the retracting lock release cylinder (85).

Even though the fastening cotter is no longer lifted due to the withdrawal of the lock lift fingers (65) (66), the fastening cotter once lifted up will not drop naturally to lock the coupler again as long as the couplers are pushed against each other between waggons.

When all the reset operations of the robot (13) are over, the finishing signal is transmitted through the solenoid control mechanism (113) to the outer control unit, which gives the reset signal to the solenoid valve (110) controlling the locating cylinder (74). Thus, it is switched to the starting position and the locating cylinder (74) extends to fold the locating fingers 68 Then, the tilt cylinder (27) receives this signal and retracts to bring the boom mechanism (12) back to the upright position while withdrawing the robot (13) from between the waggons. As soon as this operation is over, the rotary actuator (41) receives the instruction to start rotation, the robot (13) and the parallel shift links (22) are brought back to the starting position ready for the next operation. By repeating these operations, fastening cotters may be lifted successively from couplers to be separated.

Since conventional methods which are commonly applied to various control systems may also applied to the control system and the sequence mechanism for timing each of the said operations, no particular explanation will be given here. In addition, explanation has been made so far referring to an application example relating to an automatic coupler commonly employed of a type where the fastening cotter is lifted through the medium of a lock lifter by turning the release lever while holding it up. It is clear, however, that the present equipment may also be applied to couplers of other types by modifying the automatic coupling release mechanism arranged on its robot part (13).

Thus, the equipment of the present invention makes it possible in lift fastening cotters from couplers between waggons to .be separated and bring them to a position ready for release, using a relatively simple mechanism. it may not only be installed at small yards where the installation area is limited, but also results in the saving of labor and the prevention of danger, accomplishing the purposes and effects expected and stated initially.

Although explanation has been made so far referring to a preferred embodiment of the present invention, it is clear that various modifications may be practiced without deviating from the principle of the present invention. We specify, therefore, the following Scope of Claims including all such modifications which fall within the basic scope of the present invention.

What is claimed is:

1. An automatic unlocking device for rolling stock couplers, comprising a railway track which carries any rolling stock to be separated, a base stand which is installed on the ground at the railway track side, a boom mechanism which is supported by said base stand tilting freely toward the railway track and incorporating parallel shift links movable along the said railway track, a robot which is hung from said boom mechanism, and lock release devices which are arranged on the robot for unlocking couplers of any rolling stock to be separated when they are travelling on said track.

shift links for supporting the said pillar and a return member for bringing the pillar back to the starting position through the medium of the parallel-shift links.

3. Device as stated in claim 2, wherein the parallelshift links for supporting the pillar comprise two links which are supported, sliding freely, by shafts oscillating freely, crank mechanisms which are connected at the lower ends of both links so as to produce crank motion thereat, enabling the pillar supported by the upper ends of both links to move horizontally while being kept upright when they travel along the railway track, and a timing gear which connects both crank mechanisms to synchronize them.

4. Device as stated in claim 3, wherein the return member for bringing the pillar back to the starting position through the medium of the parallel shift links is a rotary actuator whose output shaft is connected to a part of said timing gear.

5. Device as stated in claim 4, wherein the robot hung from the pillar is provided with a levelling mechanism so that it may always be kept upright.

6. Device as stated in claim 5, whereinvthe levelling mechanism comprises two fluid-operated cylinders which are arranged between the base stand and the boom mechanism and between the boom mechanism and the robot, respectively. working reciprocally while exchanging their fluid.

7. An automatic unlocking device for rolling-stock couplers, comprising a railway track for the rolling stock to be separated;

support means installed laterally outwardly of said railway track;

boom means mounted on said support means and having a free end portion tilting towards said railway track, said boom means being freely pivotable so that said free end portion can move longitudinally of said railway track;

a robot device suspended from said boom means; and

lock release means arranged on said robot device and operable for unlocking the couplers of rolling stock to be separated while the rolling stock is travelling on said railway track.

8. A method of automatically unlocking the couplers of rolling stock which is travelling on a railway track, with unlocking devices mounted on a robot which is suspended from a boom that is mounted laterally adjacent the track and is pivotable on this support, comprising the steps of inserting the boom transversely of the railway track into a gap between travelling rolling stock having connected couplers, so that said robot becomes located in said gap;

pivoting said boom from a starting position in the direction of travel of said rolling stock so that said robot advances in said gap together with the rolling stock;

unlocking the couplers of the travelling rolling stock with said unlocking devices; and

withdrawing the boom and robot from said gap between the now uncoupled rolling stock.

9. A method as defined in claim 8; and further comprising the step of returning the boom to said starting position after the step of withdrawing is completed.

10. A method is defined in claim 8; and further comprising maintaining said robot substantially centered in said gap during the advancement of the robot with said rolling stock. 

1. An automatic unlocking device for rolling stock couplers, comprising a railway track which carries any rolling stock to be separated, a base stand which is installed on the ground at the railway track side, a boom mechanism which is supported by said base stand tilting freely toward the railway track and incorporating parallel shift links movable along the said railway track, a robot which is hung from said boom mechanism, and lock release devices which are arranged on the robot for unlocking couplers of any rolling stock to be separated when they are travelling on said track.
 2. Device as stated in claim 1, where the boom mechanism comprises a pillar for hanging robot, parallel-shift links for supporting the said pillar and a return member for bringing the pillar back to the starting position through the medium of the parallel-shift links.
 3. Device as stated in claim 2, wherein the parallel-shift links for supporting the pillar comprise two links which are supported, sliding freely, by shafts oscillating freely, crank mechanisms which are connected at the lower ends of both links so as to produce crank motion thereat, enabling the pillar supported by the upper ends of both links to move horizontally while being kept upright when they travel along the railway track, and a timing gear which connects both crank mechanisms to synchronize them.
 4. Device as stated in claim 3, wherein the return member for bringing the pillar back to the starting position through the medium of the parallel shift links is a rotary actuator whose output shaft is connected to a part of said timing gear.
 5. Device as stated in claim 4, wherein the robot hung from the pillar is provided with a levelling mechanism so that it may always be kept upright.
 6. Device as stated in claim 5, wherein the levelling mechanism comprises two fluid-operated cylinders which are arranged between the base stand and the boom mechanism and between the boom mechanism and the robot, respectively. working reciprocally while exchanging their fluid.
 7. An automatic unlocking device for rolling-stock couplers, comprising a railway track for the rolling stock to be separated; support means installed laterally outwardly of said railway track; boom means mounted on said support means and having a free end portion tilting towards said railway track, said boom means being freely pivotable so that said free end portion can move longitudinally of said railway track; a robot device suspended from said boom means; and lock release means arranged on said robot device and operable for unlocking the couplers of rolling stock to be separated while the rolling stock is travelling on said railway track.
 8. A method of automatically unlocking the couplers of rolling stock which is travelling on a railway track, with unlocking devices mounted on a robot which is suspended from a boom that is mounted laterally adjacent the track and is pivotable on this support, comprising the steps of inserting the boom transversely of the railway track into a gap between travelling rolling stock having connected couplers, so that said robot becomes located in said gap; pivoting said boom from a starting position in the direction of travel of said rolling stock so that said robot advances in said gap together with the rolling stock; unlocking the couplers of the travelling rolling stock with said unlocking devices; and withdrawing the boom and robot from said gap between the now uncOupled rolling stock.
 9. A method as defined in claim 8; and further comprising the step of returning the boom to said starting position after the step of withdrawing is completed.
 10. A method is defined in claim 8; and further comprising maintaining said robot substantially centered in said gap during the advancement of the robot with said rolling stock. 